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Last week, we took a look at the role incentives can play in encouraging people to buy electric vehicles (EVs). Today, we bring you a paper from the National Bureau of Economic Research that attempts to calculate the environmental benefits of EVs versus conventional vehicles in light of those subsidies. Is it as desirable to encourage EV use in a state where the electricity comes from burning coal as it is in a state where that electricity comes from natural gas or nuclear power?

The authors, four economists from the University of North Carolina (UNC) Greensboro, Dartmouth College, Middlebury College, and UNC Chapel Hill have created what they describe as "a powerful and unprecedented modeling framework for analyzing electric vehicle policy." They do this with three different components. First, a model of consumer choice between EVs and gasoline-powered cars. Next, they incorporate the effect of EV charging on air pollution from individual power stations. Finally their model compares the emissions from these power stations with the emissions internal combustion vehicles would produce at the same location.

The analysis uses some quite complicated formulae to calculate the damages that result from emissions per mile from 11 different battery EVs on sale in 2014, compared to the closest internal combustion engine-powered equivalent, independent of price. Where possible they've compared like models, so the EV Ford Focus vs a regular Focus, a Fiat 500e vs a regular Fiat 500, and so on. For cars where there isn't a conventional model (Nissan Leaf, Mitsubishi i-MiEV, Tesla's Model Ss) the authors picked cars they believed were equivalent in features (Toyota Prius, Chevrolet Spark, BMW 7-series). Then they compared the EVs' kWh/mile rating with the gasoline cars' fuel economy, as well as pollution from nitrogen oxides, sulfur dioxide, small particulates, and volatile organic compounds.

EPA city and highway mileage figures are used to calculate the effects of gasoline vehicles in urban and rural areas (their model goes down to the county level). For EVs, the authors start with EPA's MPGe figures and then adjust this for the temperature profile for each county. Then they factor in the amount of each of the pollutants listed above at each of 1,486 power stations across the country per kWh of electricity (the data is from 2010 to 2012). Those pollution estimates then get modified again by an assumed daily charging profile to calculate the emissions per mile of each power plant for any given county in the US.

The US electricity grid consists of three main regions (East, West, and Texas), which the authors further split into nine smaller regions as defined by the North American Electricity Reliability Corporation (NERC). Apparently there isn't much transmission of electricity between the main regions, but the authors assume that within the nine NERC subregions, the pollution from an EV charging will be the same regardless of the county. Finally, monetary values for the social costs of pollution come from the EPA for carbon dioxide and the AP2 model for local pollutants. And in case that wasn't enough, they weighed the statistics for vehicle miles traveled in each county to get a sense of how important driving distances are.

The result of all this complex mathematics is that, outside of a number of Californian and Texan cities, driving an EV may result in more damage from pollution than driving an equivalent conventional car. In Los Angeles, which has a lot of traffic and which benefits from relatively clean electricity, an EV is the right choice, they argue. Alternatively, the rural midwest is the opposite story, since the low population density means comparatively little air pollution from traffic, but electricity comes from lots of coal power stations. But even Chicago and New York fare badly under their model, despite both cities paying a hefty price from conventional traffic pollution.

The paper also suggests that EVs export pollution across a much larger geographical area than a gasoline vehicle. This is something that local governments don't take into account with subsidies in their view, and that the hefty EV subsidies in states like Georgia ($5,000 per EV) are based on an incomplete picture of the problem.

The conclusions are sure to be welcome news to EV skeptics; if recent discussion threads for EVs here at Ars are anything to go by, there are plenty of people out there who want to see battery-powered vehicles fail. However, there are quite a lot of assumptions made in the paper. The estimates are based on traveling 15,000 miles a year (24,000km), which is fifty percent greater than the current average for cars. And as they note, the data for power stations is now several years old, and electricity generation is becoming ever-cleaner in the US. They also haven't calculated the various impacts from mining or extracting the fuel for power stations and cars or the materials for batteries, nor the benefits to encouraging adoption of EVs now to spur the market to develop and refine powertrains and battery technology, something we're definitely seeing happen.

Promoted Comments

One massive benefit of electric cars in cities, is that the pollution isn't occurring at the point of use.

European cities have tough environmental targets to reach by 2020, and many won't make it. London, for example. Pollution within London is estimated to cause 9000+ premature deaths each year, and reduce life expectancy by over a year. Some major shopping streets have terrible NO2 levels, and solving these is paramount.

So even if the power comes from coal, that's coal burning outside the city, thus improving the air quality within the city (over a diesel or petrol car).

Other solutions require political willpower and intelligence, so it's not worth hoping that they will happen. For example Oxford Street has a bus and taxi problem (all diesel, and too many of them). A tram along the road and terminating buses early (or rerouting them) could solve the issues here. Luckily they are installing electric buses elsewhere in London now, but not in Oxford Street. Taxis should be electric soon too, but there is lifespan to consider here.

Really not surprising that cost/benefit varies by region. By extension it should not be surprising that the math will favor EVs more assuming power generation gets cleaner in the future. (which is hopefully the case).

This should not be seen as an indictment of EVs biut rather of the continued use of coal for power generation in many regions.

The article basically says that EVs are only as green as the production of their electricity.Oddly enough, not everybody likes this conclusion.

Considering that EVs can be great at absorbing 'unreliable' green electicity,considering that PV and wind are already on cost parity with fossil fuels,considering that fossil fuels are 'too cheap' today because the externalities are unaccounted for,

This ARS article was greatly conveyed. but the study itself is completely flawed in their comparisons.

I read this study last week when it broke out and couldn't wait to discuss on Ars. The study is comparing Gasoline to Power generation to get the EPA value of a car. THIS IS A FLAWED COMPARISON.

You can not compare in this way. The only way you could compare if you are doing emissions from a Gasoline engine, is to directly compare the different cars. an All electric car makes zero emissions, so it wins, end of study.

if you want to take one step back and see how the electric car gets it power, then you also have to take one step back at how the Gasoline car (ICE Car) gets its power. I live in southeast texas, where some order of 20-40% of the countries oil supply is processed into Gasoline for the USA, diesel fuel, Jet fuel, and NG is liquefied with additives to be shipped as LNG, and or imported from all reaches of the planet.

These processing plants require HUGE sums of power and pollute unimpeded by the EPA. I don't have any figures but to create one gallon of nice rich 93 octane Gasoline for your pretty BMW-7 series that also produces emissions once it burns it in its own engine, then you also need to take into account the emission produced by the Fracking and oil drilling process, the Shipping vessel to bring it to port, the enormous amounts of power generation required to power the processing plant, the processing plant itself, which uses Coal and other products to produce the gas, the enormous amount of energy it takes to run the pumping station to pump the product to Baytown, TX, then the even large amount of energy to pump that to all parts of the country. And once it gets there, each gas station company adds its own additive and then it has to be trucked to the gas-station it gets picked up at.

so since a coal fired plant can directly mine/extract the coal and then fire it in a fairly clean fired coal plant. (clean compared to years past, even the coal industry says they are getting cleaner). I'd take power generation directly to zero emission vehicle over ICE car any day, with orders of magnitude cleaner emissions if you considered the facts for what they were.

Just use a quantitative value by adding all the emissions to get your one gallon, so it can be included in the ICE comparison since this was done for the EV's.

The Telsa batteries come with an 8 year warranty, so I would have to replace them every 8 years at $12,000. Mabye I would get lucky and wear them out before the 8 years is up, but I doubt it is a replacement value warranty. It is most likely a percentage of life left, which means I would be paying sooner with all the miles I drive.

Battery longevity is directly related to temperature, depth of discharge, and time spent at particularly high and particularly low states of charge. As a result, EV manufacturers lock out the highest and lowest states of charge. At 60% depth of discharge which corresponds to an average of 150 miles of range, and avoiding high and low states of charge, Panasonic has shown similar NCA cells to last over 3,000 charge cycles with a degradation to about 88%. 150 * 3,000 = 450,000 miles. Using a 90% DoD with 1,200 charge cycles, we are looking at about 250,000 miles. At 250,000 miles, at 20,000 miles a year, that's 12.5 years. That's why the unlimited mile warranty with the 85 kWh battery pack in the 8 year term. You'd have to drive over 30,000 miles a year to even start to test the limits of longevity in 8 years, and it is likely that the mean is going to be somewhere around 40,000 to 45,000 miles a year to drop the battery down to the mid 80% capacity. At that point, you can still choose to drive the car.

If you take the same cells and charge to 100% and discharge to almost 0% repeatedly you are likely to get something like 300 charge cycles before depleting to 80% capacity. That's why no EV manufacturers make sure the battery management systems do not allow those scenarios.

That mostly went out with the 80's and almost entirely by 2000; everything is a combination of aluminum and plastic or aluminum and carbon fiber now (or aluminum alloy, titanium, and carbon fiber for the really pricey sports cars).

I can't imagine where you come up with this statement.

On average, cars built today are about 75% steel by weight.

Perhaps you can name even one major mass market car that is mostly aluminum and/or plastic by weight?

Sorry new to this line of thought in this thread but doesn't that article just say they are increasing the amount of aluminum in the F-150? It doesn't appear to give percentages of use within a vehicle, rather it gives percent increase which is a stat I hate if they don't provide the baseline.

If you drink that almond milk it increases your chance of getting cancer 380%!*

*Original chance of getting cancer = 0.000000000000000000000000000000000000000000001, now it is 0.000000000000000000000000000000000000000002.

When you save 700 lbs - or about 15% of total weight - by switching from steel to aluminum, you're doing a lot more than fiddling with third decimal points. It may not be 100% aluminum, but it is a very significant amount.

Sure but that does not preclude the possibility that it is still 75% steel. They have not given any figures. If they saved 15% of total weight adding in aluminum replacements that still leaves the possibility that most of the weight of the remaining percentage is mainly constituted of steel.

My decimal point argument was merely to point out that when an article or individual cites a percentage increase without providing baseline hard numbers it is pointless.

That mostly went out with the 80's and almost entirely by 2000; everything is a combination of aluminum and plastic or aluminum and carbon fiber now (or aluminum alloy, titanium, and carbon fiber for the really pricey sports cars).

I can't imagine where you come up with this statement.

On average, cars built today are about 75% steel by weight.

Perhaps you can name even one major mass market car that is mostly aluminum and/or plastic by weight?

Sorry new to this line of thought in this thread but doesn't that article just say they are increasing the amount of aluminum in the F-150? It doesn't appear to give percentages of use within a vehicle, rather it gives percent increase which is a stat I hate if they don't provide the baseline.

If you drink that almond milk it increases your chance of getting cancer 380%!*

*Original chance of getting cancer = 0.000000000000000000000000000000000000000000001, now it is 0.000000000000000000000000000000000000000002.

When you save 700 lbs - or about 15% of total weight - by switching from steel to aluminum, you're doing a lot more than fiddling with third decimal points. It may not be 100% aluminum, but it is a very significant amount.

Sure but that does not preclude the possibility that it is still 75% steel. They have not given any figures. If they saved 15% of total weight adding in aluminum replacements that still leaves the possibility that most of the weight of the remaining percentage is mainly constituted of steel.

My decimal point argument was merely to point out that when an article or individual cites a percentage increase without providing baseline hard numbers it is pointless.

It's only pointless to you if you don't know the baseline numbers. Quit tossing around your ignorance like it's the end-all, be-all of all positions. At a minimum, do some math. Here: best case scenario: aluminum weighs nothing. Everything else is steel. A reduction of 15% in weight means that 15% of overall steel has been replaced by aluminum. But we know that aluminum weighs 30% of the same volume of steel. So know we know that if all Ford did was replace steel structures with aluminum, 20% of the total steel has been replaced by aluminum. Now you get into the finer details: how much does everything weigh that isn't steel? How much does the frame of an F150 weigh? How much does the engine block weigh (which, btw, is also transitioning to aluminum)? I'm not going to do an extensive research for you into this, but the numbers are available, even if you have to do some digging.

Yeah, I get annoyed when people claim ignorance on a topic and then position it as some sort of insightful comment. Why do you ask?

When you save 700 lbs - or about 15% of total weight - by switching from steel to aluminum, you're doing a lot more than fiddling with third decimal points. It may not be 100% aluminum, but it is a very significant amount.

Quote:

Sure but that does not preclude the possibility that it is still 75% steel. They have not given any figures. If they saved 15% of total weight adding in aluminum replacements that still leaves the possibility that most of the weight of the remaining percentage is mainly constituted of steel.

My decimal point argument was merely to point out that when an article or individual cites a percentage increase without providing baseline hard numbers it is pointless.

Quote:

It's only pointless to you if you don't know the baseline numbers. Quit tossing around your ignorance like it's the end-all, be-all of all positions. At a minimum, do some math. Here: best case scenario: aluminum weighs nothing. Everything else is steel. A reduction of 15% in weight means that 15% of overall steel has been replaced by aluminum. But we know that aluminum weighs 30% of the same volume of steel. So know we know that if all Ford did was replace steel structures with aluminum, 20% of the total steel has been replaced by aluminum. Now you get into the finer details: how much does everything weigh that isn't steel? How much does the frame of an F150 weigh? How much does the engine block weigh (which, btw, is also transitioning to aluminum)? I'm not going to do an extensive research for you into this, but the numbers are available, even if you have to do some digging.

Yeah, I get annoyed when people claim ignorance on a topic and then position it as some sort of insightful comment. Why do you ask?

Man, rudeness....

When I said new to this line of thought, I meant not involved in this part of the thread, not ignorant, so shut it. New to the discussion does not equal new to the subject...

Also, my point was the article you so snidely linked with your "I'll just leave this here..." quip failed to prove anything.

The other guy said that 75% of vehicles are still composed of steel, then you linked something that proved nothing at all.

You are the one acting ignorantly.

The article you linked only stated that the F-150 only increased the amount of aluminum it uses, saying nothing about the total amount.

So perhaps you are the one you should be annoyed at.

Another even pointed that out (Alhazred), stating that the F150 disproves your stupid point, given how revolutionary it is, yet still has a lot of steel in it.

What do you know, the liberal push to force everyone into EVs turns out to be a hoax. Yet another lie in the big ball of lies that is global warming (care to comment on the hockey stick now Algore?) I hope to hear this one on Rush at work today.

"Algore?"

I don't even know what to say to you. You're trolling, right?

Well, considering that a third of his posting history has been modded...

Actually, that only proves that he is being persecuted. He sees the truth, man. OPEN YOUR EYES!

That mostly went out with the 80's and almost entirely by 2000; everything is a combination of aluminum and plastic or aluminum and carbon fiber now (or aluminum alloy, titanium, and carbon fiber for the really pricey sports cars).

I can't imagine where you come up with this statement.

On average, cars built today are about 75% steel by weight.

Perhaps you can name even one major mass market car that is mostly aluminum and/or plastic by weight?

Sorry new to this line of thought in this thread but doesn't that article just say they are increasing the amount of aluminum in the F-150? It doesn't appear to give percentages of use within a vehicle, rather it gives percent increase which is a stat I hate if they don't provide the baseline.

If you drink that almond milk it increases your chance of getting cancer 380%!*

*Original chance of getting cancer = 0.000000000000000000000000000000000000000000001, now it is 0.000000000000000000000000000000000000000002.

When you save 700 lbs - or about 15% of total weight - by switching from steel to aluminum, you're doing a lot more than fiddling with third decimal points. It may not be 100% aluminum, but it is a very significant amount.

In the final reckoning, they saved about 300 lbs, because they also increased the overall size and hauling/towing capacity.

I kind of wish you could still buy a small Ranger (or Toyota Hilux) instead of these ever-expanding pickups, they'd probably get insane mpg with modern materials and design, but I guess those won't sell anymore. Something small like that is as much as I'd ever need.

All personal vehicles seem to have been slowly growing. I owned a 1989 Honda Accord, and then a 2003 Honda Accord. Except for the Model name, you never would have guessed they were supposed to be the same lineage. And it wasn't just styling changes (which you'd expect between two models that far apart). The model took a whole step up in size classification, IIRC. From "compact" to "mid-size" (or something like that). And actually my 2003 got slightly worse gas mileage than my 1989. Since the 2003 was a much bigger/heavier car, that really meant that all the mileage improvements went into making the car bigger, rather than into making a same sized car use less gas. I didn't really want that big a car in 2003, but the smaller car (Civic, in the case of Honda) just wasn't as nice a car as I wanted. If the Civic had otherwise been as nice as a car as the Accord (just smaller), I'd have bought the smaller car. But, obviously, I was in the minority... or Honda probably would have offered me what I wanted.

I read a lot of the replies and one sticks out the most as not having a good understanding. The post from Bonehead citing that because the warranty for the EV battery car is 8 years, that he would have to buy a new battery every eight years @ 12k.

First, if your TV has a warranty of 3 years, to you get a new TV every 3 years? Do you buy a new engine for your ICE car after the 5 (or 6) year warranty runs out? I know of MANY people with a Prius that is over 10 years old and still on the original battery. The reason the EV battery warranty is 8 years is because the MFG is pretty certain very few will actually collect on that warranty.

Props to the couple of posters who went behind the ugly curtain of what it takes to produce a gallon of gas from the refining process. As touched on, the oil refining process is a nasty and power hungry process.

Refining oil creates a byproduct called coke. The United States will no longer allow this substance to be disposed of inside its borders. So even after you have that gallon of gas to burn into the atmosphere, the by-product is being shipped off to a third World country that will take our trash for a price.

I read a lot of the replies and one sticks out the most as not having a good understanding. The post from Bonehead citing that because the warranty for the EV battery car is 8 years, that he would have to buy a new battery every eight years @ 12k.

First, if your TV has a warranty of 3 years, to you get a new TV every 3 years? Do you buy a new engine for your ICE car after the 5 (or 6) year warranty runs out? I know of MANY people with a Prius that is over 10 years old and still on the original battery. The reason the EV battery warranty is 8 years is because the MFG is pretty certain very few will actually collect on that warranty.

I was one of the ones referencing the battery wearing out in 8 years. I drive about 38,000 miles per year, which is almost 4 times the norm. How long do you think that battery would last for me? I'm guessing a battery for me wouldn't last 8 years.

Until they come out with solid state batteries that last 50 years, I don't think it is good to compare it to a TV that is mostly solid state components.

I read a lot of the replies and one sticks out the most as not having a good understanding. The post from Bonehead citing that because the warranty for the EV battery car is 8 years, that he would have to buy a new battery every eight years @ 12k.

First, if your TV has a warranty of 3 years, to you get a new TV every 3 years? Do you buy a new engine for your ICE car after the 5 (or 6) year warranty runs out? I know of MANY people with a Prius that is over 10 years old and still on the original battery. The reason the EV battery warranty is 8 years is because the MFG is pretty certain very few will actually collect on that warranty.

I was one of the ones referencing the battery wearing out in 8 years. I drive about 38,000 miles per year, which is almost 4 times the norm. How long do you think that battery would last for me? I'm guessing a battery for me wouldn't last 8 years.

Until they come out with solid state batteries that last 50 years, I don't think it is good to compare it to a TV that is mostly solid state components.

Wouldn't the warranty cover you then during those 8 years? Sounds like you'd get 1 or 2 free replacements during that timeframe.

I read a lot of the replies and one sticks out the most as not having a good understanding. The post from Bonehead citing that because the warranty for the EV battery car is 8 years, that he would have to buy a new battery every eight years @ 12k.

First, if your TV has a warranty of 3 years, to you get a new TV every 3 years? Do you buy a new engine for your ICE car after the 5 (or 6) year warranty runs out? I know of MANY people with a Prius that is over 10 years old and still on the original battery. The reason the EV battery warranty is 8 years is because the MFG is pretty certain very few will actually collect on that warranty.

I was one of the ones referencing the battery wearing out in 8 years. I drive about 38,000 miles per year, which is almost 4 times the norm. How long do you think that battery would last for me? I'm guessing a battery for me wouldn't last 8 years.

Until they come out with solid state batteries that last 50 years, I don't think it is good to compare it to a TV that is mostly solid state components.

This ARS article was greatly conveyed. but the study itself is completely flawed in their comparisons.

I read this study last week when it broke out and couldn't wait to discuss on Ars. The study is comparing Gasoline to Power generation to get the EPA value of a car. THIS IS A FLAWED COMPARISON.

You can not compare in this way. The only way you could compare if you are doing emissions from a Gasoline engine, is to directly compare the different cars. an All electric car makes zero emissions, so it wins, end of study.

if you want to take one step back and see how the electric car gets it power, then you also have to take one step back at how the Gasoline car (ICE Car) gets its power. I live in southeast texas, where some order of 20-40% of the countries oil supply is processed into Gasoline for the USA, diesel fuel, Jet fuel, and NG is liquefied with additives to be shipped as LNG, and or imported from all reaches of the planet.

These processing plants require HUGE sums of power and pollute unimpeded by the EPA. I don't have any figures but to create one gallon of nice rich 93 octane Gasoline for your pretty BMW-7 series that also produces emissions once it burns it in its own engine, then you also need to take into account the emission produced by the Fracking and oil drilling process, the Shipping vessel to bring it to port, the enormous amounts of power generation required to power the processing plant, the processing plant itself, which uses Coal and other products to produce the gas, the enormous amount of energy it takes to run the pumping station to pump the product to Baytown, TX, then the even large amount of energy to pump that to all parts of the country. And once it gets there, each gas station company adds its own additive and then it has to be trucked to the gas-station it gets picked up at.

so since a coal fired plant can directly mine/extract the coal and then fire it in a fairly clean fired coal plant. (clean compared to years past, even the coal industry says they are getting cleaner). I'd take power generation directly to zero emission vehicle over ICE car any day, with orders of magnitude cleaner emissions if you considered the facts for what they were.

Just use a quantitative value by adding all the emissions to get your one gallon, so it can be included in the ICE comparison since this was done for the EV's.

Disclaimer: I have not read the actual study, just the Ars article.

From the synopsis that Ars has it appears that the study did not go into the materials needed to produce the car batteries. While I think that you are right that they should take into account the costs of drilling and refining the oil, in doing so they also need to factor in the mining and processing of the raw materials of the batteries for an electric car. I think if you factor that in, the harm is going to be closer than you think. A typical oil well bore is in the range of 1/2 a foot in diameter and a couple hundred feet deep. Whereas, I believe that mining for the nickel, cobalt, and/or lithium used in the batteries is a bit more intrusive:

Additionally, the smelting process for the metals is an order of magnitude higher for metals as well just factoring in the energy input requirements to process those materials over crude, and the amount of waste generated by each process. Nearly every part of crude is put to some use. That really can't be said for the mining process. Being a former nuclear submariner I am well schooled in the power generation processes and the efficiencies (and inefficiencies) associated with those processes. For instance an average efficiency of a combustion engine is around 20%, but that is a direct fuel to power conversion. In calculating the similar efficiency of a hybrid you need to account for the efficency of the power generation (around 40%), power grid (95%), charging (85%), and electric car (around 85% for electric motors). That puts the effficiency of the power cycle in a car battery at around 25-30% - which is nearly the same as that of a combustion engine.

My point is thus: it is great to be an environmentally aware individual, but that requires knowledge as to the actual environmental of the entire chain, not just self serving portions that allow you to conveniently be blind to the effects of your activities. This study is the first I have read about that makes the attempt. It falls somewhat short of being comprehensive, but the feel-good Prius drivers should at least take notice that maybe they aren't quite part of the solution yet.

This ARS article was greatly conveyed. but the study itself is completely flawed in their comparisons.

I read this study last week when it broke out and couldn't wait to discuss on Ars. The study is comparing Gasoline to Power generation to get the EPA value of a car. THIS IS A FLAWED COMPARISON.

You can not compare in this way. The only way you could compare if you are doing emissions from a Gasoline engine, is to directly compare the different cars. an All electric car makes zero emissions, so it wins, end of study.

if you want to take one step back and see how the electric car gets it power, then you also have to take one step back at how the Gasoline car (ICE Car) gets its power. I live in southeast texas, where some order of 20-40% of the countries oil supply is processed into Gasoline for the USA, diesel fuel, Jet fuel, and NG is liquefied with additives to be shipped as LNG, and or imported from all reaches of the planet.

These processing plants require HUGE sums of power and pollute unimpeded by the EPA. I don't have any figures but to create one gallon of nice rich 93 octane Gasoline for your pretty BMW-7 series that also produces emissions once it burns it in its own engine, then you also need to take into account the emission produced by the Fracking and oil drilling process, the Shipping vessel to bring it to port, the enormous amounts of power generation required to power the processing plant, the processing plant itself, which uses Coal and other products to produce the gas, the enormous amount of energy it takes to run the pumping station to pump the product to Baytown, TX, then the even large amount of energy to pump that to all parts of the country. And once it gets there, each gas station company adds its own additive and then it has to be trucked to the gas-station it gets picked up at.

so since a coal fired plant can directly mine/extract the coal and then fire it in a fairly clean fired coal plant. (clean compared to years past, even the coal industry says they are getting cleaner). I'd take power generation directly to zero emission vehicle over ICE car any day, with orders of magnitude cleaner emissions if you considered the facts for what they were.

Just use a quantitative value by adding all the emissions to get your one gallon, so it can be included in the ICE comparison since this was done for the EV's.

Disclaimer: I have not read the actual study, just the Ars article.

From the synopsis that Ars has it appears that the study did not go into the materials needed to produce the car batteries. While I think that you are right that they should take into account the costs of drilling and refining the oil, in doing so they also need to factor in the mining and processing of the raw materials of the batteries for an electric car. I think if you factor that in, the harm is going to be closer than you think. A typical oil well bore is in the range of 1/2 a foot in diameter and a couple hundred feet deep. Whereas, I believe that mining for the nickel, cobalt, and/or lithium used in the batteries is a bit more intrusive:

Additionally, the smelting process for the metals is an order of magnitude higher for metals as well just factoring in the energy input requirements to process those materials over crude, and the amount of waste generated by each process. Nearly every part of crude is put to some use. That really can't be said for the mining process. Being a former nuclear submariner I am well schooled in the power generation processes and the efficiencies (and inefficiencies) associated with those processes. For instance an average efficiency of a combustion engine is around 20%, but that is a direct fuel to power conversion. In calculating the similar efficiency of a hybrid you need to account for the efficency of the power generation (around 40%), power grid (95%), charging (85%), and electric car (around 85% for electric motors). That puts the effficiency of the power cycle in a car battery at around 25-30% - which is nearly the same as that of a combustion engine.

My point is thus: it is great to be an environmentally aware individual, but that requires knowledge as to the actual environmental of the entire chain, not just self serving portions that allow you to conveniently be blind to the effects of your activities. This study is the first I have read about that makes the attempt. It falls somewhat short of being comprehensive, but the feel-good Prius drivers should at least take notice that maybe they aren't quite part of the solution yet.

1) You've excluded refining (and transport) for gasoline, aka upstream, in your 20% ICE versus 25-30% EV efficiency "analysis"; the same flaw in many papers (non-peer reviewed) where they get away with comparing tank-to-wheels for gasoline to well-to-wheels for electric. Not science, that's cherry picking rather than apples to apple.

2) Comparing mining of materials (which can and will be re-used and recycled) to mining of fuel (petroluem) which is burned once (while polluting through entire life cycle)

3) First study you've heard of??! This just means you aren't reading enough. There are dozens and dozens of EV vs ICE life cycle studies and analysis; all concluded that non-coal (or low coal) generation more than overcomes the additional emissions created by the EVs battery manufacturing. Here's one of many:

Here's what researchers from ANL (Argonne National Laboratory) conclude on the life cycle impacts of lithium mining and battery production. The main points are:

1) Batteries are small contributors to life-cycle energy use and CO2 emissions

2) Impacts from lithium "mining" (brine extraction) production are minimal

Boneman69: Until they come out with solid state batteries that last 50 years, I don't think it is good to compare it to a TV that is mostly solid state components.

Boneman, First, isn't a battery SOLID STATE?, but secondly, that pretty much misses my entire point. It was more about the purpose and usage of a warranty. (for anything). Warranties are not telling you when something is going to wear out or fail... they are simply guarantees, that if something does happen during that time, you are simply covered. It is a no worries deal, with a time limit. But no one says you can't get 15 or 20 years from the battery.

I was one of the Prius owners who kept the car over 10 years. I bought when people said Hybrids will never catch on, they definitely were NOT cool in 1995, but I never had a lick of trouble with it. I hated the car, but it was a faithful driving machine.

Boneman, I forgot to add one more small detail... guess why the battery is warranted for 8 years? The miles you drive have no relevance. It is UNLIMITED mileage, because???? Miles don't matter on an EV. It is hard for people to not think in terms of ICE (wear and tear), but the rules have changed. Parking the car for a month probably wears on the battery as much as driving it 200 miles a day.

Boneman, I forgot to add one more small detail... guess why the battery is warranted for 8 years? The miles you drive have no relevance. It is UNLIMITED mileage, because???? Miles don't matter on an EV. It is hard for people to not think in terms of ICE (wear and tear), but the rules have changed. Parking the car for a month probably wears on the battery as much as driving it 200 miles a day.

For a high mileage driver as yourself, this is an appealing deal.

Well only the Tesla (which starts at $63,700 net after federal tax) has the 8 year unlimited mile warranty; all others (LEAF, Volt, etc) have 8 years or 100,000 miles, whichever comes first. Still your point is valid, and their are plenty of Volts with well over 100k miles running around operating as good as day one battery-wise. The LEAFs haven't fared as well, some showing 20%+ degradation of range and some charging performance issues in only 50k miles in some cases; but this seems to be very specific to the LEAFs engineering (or lack thereof) and not indicative of better engineered models by GM (Spark EV), Tesla, BMW, many/most others that have liquid cooling/warming of the batteries. Duh Nissan automotive engineers!

You're right. 100k is still very good, so it figures ICE MFG's are still thinking in terms of wear and tear too It stands to reason and maybe they expect more people will relate with a given mileage, not to mention it does reduce their exposure over the long haul.

This ARS article was greatly conveyed. but the study itself is completely flawed in their comparisons.

I read this study last week when it broke out and couldn't wait to discuss on Ars. The study is comparing Gasoline to Power generation to get the EPA value of a car. THIS IS A FLAWED COMPARISON.

You can not compare in this way. The only way you could compare if you are doing emissions from a Gasoline engine, is to directly compare the different cars. an All electric car makes zero emissions, so it wins, end of study.

if you want to take one step back and see how the electric car gets it power, then you also have to take one step back at how the Gasoline car (ICE Car) gets its power. I live in southeast texas, where some order of 20-40% of the countries oil supply is processed into Gasoline for the USA, diesel fuel, Jet fuel, and NG is liquefied with additives to be shipped as LNG, and or imported from all reaches of the planet.

These processing plants require HUGE sums of power and pollute unimpeded by the EPA. I don't have any figures but to create one gallon of nice rich 93 octane Gasoline for your pretty BMW-7 series that also produces emissions once it burns it in its own engine, then you also need to take into account the emission produced by the Fracking and oil drilling process, the Shipping vessel to bring it to port, the enormous amounts of power generation required to power the processing plant, the processing plant itself, which uses Coal and other products to produce the gas, the enormous amount of energy it takes to run the pumping station to pump the product to Baytown, TX, then the even large amount of energy to pump that to all parts of the country. And once it gets there, each gas station company adds its own additive and then it has to be trucked to the gas-station it gets picked up at.

so since a coal fired plant can directly mine/extract the coal and then fire it in a fairly clean fired coal plant. (clean compared to years past, even the coal industry says they are getting cleaner). I'd take power generation directly to zero emission vehicle over ICE car any day, with orders of magnitude cleaner emissions if you considered the facts for what they were.

Just use a quantitative value by adding all the emissions to get your one gallon, so it can be included in the ICE comparison since this was done for the EV's.

Disclaimer: I have not read the actual study, just the Ars article.

From the synopsis that Ars has it appears that the study did not go into the materials needed to produce the car batteries. While I think that you are right that they should take into account the costs of drilling and refining the oil, in doing so they also need to factor in the mining and processing of the raw materials of the batteries for an electric car. I think if you factor that in, the harm is going to be closer than you think. A typical oil well bore is in the range of 1/2 a foot in diameter and a couple hundred feet deep. Whereas, I believe that mining for the nickel, cobalt, and/or lithium used in the batteries is a bit more intrusive:

Additionally, the smelting process for the metals is an order of magnitude higher for metals as well just factoring in the energy input requirements to process those materials over crude, and the amount of waste generated by each process. Nearly every part of crude is put to some use. That really can't be said for the mining process. Being a former nuclear submariner I am well schooled in the power generation processes and the efficiencies (and inefficiencies) associated with those processes. For instance an average efficiency of a combustion engine is around 20%, but that is a direct fuel to power conversion. In calculating the similar efficiency of a hybrid you need to account for the efficency of the power generation (around 40%), power grid (95%), charging (85%), and electric car (around 85% for electric motors). That puts the effficiency of the power cycle in a car battery at around 25-30% - which is nearly the same as that of a combustion engine.

My point is thus: it is great to be an environmentally aware individual, but that requires knowledge as to the actual environmental of the entire chain, not just self serving portions that allow you to conveniently be blind to the effects of your activities. This study is the first I have read about that makes the attempt. It falls somewhat short of being comprehensive, but the feel-good Prius drivers should at least take notice that maybe they aren't quite part of the solution yet.

1) You've excluded refining (and transport) for gasoline, aka upstream, in your 20% ICE versus 25-30% EV efficiency "analysis"; the same flaw in many papers (non-peer reviewed) where they get away with comparing tank-to-wheels for gasoline to well-to-wheels for electric. Not science, that's cherry picking rather than apples to apple.

2) Comparing mining of materials (which can and will be re-used and recycled) to mining of fuel (petroluem) which is burned once (while polluting through entire life cycle)

3) First study you've heard of??! This just means you aren't reading enough. There are dozens and dozens of EV vs ICE life cycle studies and analysis; all concluded that non-coal (or low coal) generation more than overcomes the additional emissions created by the EVs battery manufacturing. Here's one of many:

Here's what researchers from ANL (Argonne National Laboratory) conclude on the life cycle impacts of lithium mining and battery production. The main points are:

1) Batteries are small contributors to life-cycle energy use and CO2 emissions

2) Impacts from lithium "mining" (brine extraction) production are minimal

I didn't miss out the refining and upstream production of gasoline. Do you think that the grid is powered without this as well? It appears to generally be a cost incurred in both chains (gas from well to tank vs. (gas/coal to power plants to produce energy + nuclear + wind + solar). I just think the wind/solar/nuclear component is negligible compared to grid energy production vs. coal/gas turbine plants. You can debate me on that, but you have to include that in the analysis of the electric if you are including the production of gas in the analysis of an internal combustion engine.

Not all cars use lithium batteries, many use NiMH instead (e.g., Toyota Prius, Honda Insight, and Honda Civic). Heat dissipation due to charging and discharging operations is not a "small contributor" to the energy expenditure of a battery each charge/discharge cycle is only about 85% (each way) and the efficiency of the charge/discharge reduces over battery life with each cycle. Those that do, most do not recycle the lithium in the batteries as it is cheaper to simply mine more (through the brine operations mentioned).

As for this being the first study that I heard of, I think you missed the rest of that sentence. There are some that have compared the efficiencies of each product, but this was the one in which it looked at more than just the battery to wheel comparison for an electric vehicle, including grid efficiency, etc. Most studies that I have seen want to maximize the efficiency of the electric car and this do not include that little fact or give it the waive of a hand.

I didn't miss out the refining and upstream production of gasoline. Do you think that the grid is powered without this as well?

Yes you did, in our own words you wrote "efficiency of a combustion engine is around 20%, but that is a direct fuel to power conversion", which is pretty easily confirmed as correct for real world driving, but you omitted refining and transport), around 6kWh of polluting energy lost in refining or an addition 15% off the top according to Argonne National Laboratory, however you look at it.

Try REALLY HARD to understand the difference between tank-to-wheels (which you used for gas) and well-to-wheels (which I use for BOTH gasoline and electric), because you still showing that you're just not getting it. It is, to put it simply, all upstream plus all downstream for the fueling cycle. Both upstream (example: refining) and downstream (combustion) for gasoline pollute and have losses. Only upstream (electricity generation) for electric pollutes, but both stages also have losses. And batteries, manufacturing, etc, is not part of this analysis, they are examined in a full life cycle analysis, of which the well-to-wheels is just one part...and the most significant and polluting part for an gasoline internal combustion engine.

I just think the wind/solar/nuclear component is negligible compared to grid energy production vs. coal/gas turbine plants. You can debate me on that

Think what you want, you're wrong. There is is no debate when your facts are incorrect. Nuclear and renewable are full 1/3 of all grid power in the US. Look it up on eia dot gov. It's a fact. And then natural gas makes up an additional over 25% and is much cleaner well-to-wheels powering an electric car than gasoline. Another unshakable fact confirmed by the scientific studies you claim don't exist.

In my state, it's 49% nuclear AND also the base load overnight, when most electric cars charge. And yes, in some states the baseload it coal, not going to lie. So how much an electric car pollutes mainly depends on where you live, and/or what power you buy (or generate yoursel with home solar, or some people even home wind)

Not all cars use lithium batteries, many use NiMH instead (e.g., Toyota Prius, Honda Insight, and Honda Civic).

All modern plug in cars old since 2010, all 300,000+ of them in the US use lithium batteries. You're confused by mixing in cars that are non-plug in hybrids and of a legacy design. Most of those used NiMH, and some like the Prius non-plug in product line still do. They only run on gasoline with regenerative braking. Zero grid power. Go bash a Prius forum about those if you like, but as far as plug in electric vehicles you are simply misinformed.

this was the one in which it looked at more than just the battery to wheel comparison for an electric vehicle, including grid efficiency, etc. Most studies that I have seen want to maximize the efficiency of the electric car and this do not include that little fact or give it the waive of a hand.

That's simply not true, all scientific studies on electric car emissions are at least well-to-wheels, if not life cycle...you're a "treasure trove" of propaganda and misinformation...but I guess everyone needs a hobby...

I read a lot of the replies and one sticks out the most as not having a good understanding. The post from Bonehead citing that because the warranty for the EV battery car is 8 years, that he would have to buy a new battery every eight years @ 12k.

First, if your TV has a warranty of 3 years, to you get a new TV every 3 years? Do you buy a new engine for your ICE car after the 5 (or 6) year warranty runs out? I know of MANY people with a Prius that is over 10 years old and still on the original battery. The reason the EV battery warranty is 8 years is because the MFG is pretty certain very few will actually collect on that warranty.

I was one of the ones referencing the battery wearing out in 8 years. I drive about 38,000 miles per year, which is almost 4 times the norm. How long do you think that battery would last for me? I'm guessing a battery for me wouldn't last 8 years.

Until they come out with solid state batteries that last 50 years, I don't think it is good to compare it to a TV that is mostly solid state components.

Wouldn't the warranty cover you then during those 8 years? Sounds like you'd get 1 or 2 free replacements during that timeframe.

I'm sure the warranty is not a replacement warranty, but a pro-rated warranty, like tires. I'm not sure, but I can't imagine otherwise.

I'm sure the warranty is not a replacement warranty, but a pro-rated warranty, like tires. I'm not sure, but I can't imagine otherwise.

It is a replacement warranty, but replacement with new battery for defect/failure (car won't drive) only within 8 year/100k miles. It is not a warranty against degradation, though each manufacturer has opted to formally or informally specify additional degradation conditions under which a replacement or repair of battery/cells would be given (a kind of second warranty if you will). Here's Nissan's:

"Nissan will repair or replace a Leaf's battery within five years or 60,000 miles if it loses more than 30 percent of its charge capacity. For Leaf owners, that means the warranty kicks in if the 12-bar battery gauge falls under nine bars. The new warranty is the second for the Leaf's batteries; the first covers defects and flaws for up to eight years or 100,000 miles."

I'm sure the warranty is not a replacement warranty, but a pro-rated warranty, like tires. I'm not sure, but I can't imagine otherwise.

It is a replacement warranty, but replacement with new battery for defect/failure (car won't drive) only within 8 year/100k miles. It is not a warranty against degradation, though each manufacturer has opted to formally or informally specify additional degradation conditions under which a replacement or repair of battery/cells would be given (a kind of second warranty if you will). Here's Nissan's:

"Nissan will repair or replace a Leaf's battery within five years or 60,000 miles if it loses more than 30 percent of its charge capacity. For Leaf owners, that means the warranty kicks in if the 12-bar battery gauge falls under nine bars. The new warranty is the second for the Leaf's batteries; the first covers defects and flaws for up to eight years or 100,000 miles."

Further, Well to Well (WtW) calculations are pretty complex, so that's why any decent research paper usually leverages the Argonne National Labs GREET model that is likely the most comprehensive WtW calculator:

The big problem with the paper referenced in the article is that they use GREET for only a portion of their analysis and ignores the WtW for the gasoline side, which makes the paper fraudulent in my mind. It isn't ignorance since they know about WtW calculations with the GREET and through other papers, but they chose to ignore it anyways and then make PR claims from their resulting garbage output. Then various media outlets pick up on the PR claims and so I'm doubly disappointed in Ars for letting that slide through.

All this is combined together at fueleconomy.gov which allows you to compare WtW greenhouse gas emissions of various vehicles and put in your zip code to select the regional market. It's not LCA, but you can see that picture from various research papers and the Mercedes LCA.

The end result of all of this supports the case for BEVs after factoring in both WtW and LCA for both greenhouse gas emissions and energy efficiency. That's factoring in pretty much everything including things like transport of coal, various power plant efficiencies, charging losses, transmission line losses, and so forth. It's truly very clear when you examine the data. The number one issue for BEVs that is a loss is when there is high coal usage, particulate emissions can be higher or even. That's partially because various coal plants have resisted putting in the mandated pollution controls which are expensive and may push some of these plants into economic insolvency with the primary driver being low natural gas costs which means its cheaper to just switch to natural gas. There are also additional ripple effects, as we actually don't have enough overnight base load to help keep wind and nuclear options on better economic footing. A high adoption of plug-ins may actually help push for better, more efficient baseload generation options including making a better case for wind and keeping our nuclear plants online. In addition, much of our new electricity production that has been coming online lately has been renewable sources. So BEVs will get cleaner over their lifespan.

I think if you factor that in, the harm is going to be closer than you think. A typical oil well bore is in the range of 1/2 a foot in diameter and a couple hundred feet deep.

I'll see your photo and raise you;

I give you... the Tar Sands... a little bigger than 1/2 a foot...

For the fate of humans and the fate of animals is the same; as one dies, so dies the other. They all have the same breath, and humans have no advantage over the animals; for all is vanity. -- Ecclesiastes 3:19

I could not easily find exact difference they claim but I found on page 83 of their PDF, for example for Tesla S (85 kWh) , where they say electric 'environmental cost' is 2.96 , while gasoline is 'only' 2.89 (in cents per mile) - in other words, they claim that electric is 2% worse.

I could not easily find exact difference they claim but I found on page 83 of their PDF, for example for Tesla S (85 kWh) , where they say electric 'environmental cost' is 2.96 , while gasoline is 'only' 2.89 (in cents per mile) - in other words, they claim that electric is 2% worse.

Using that in above case would turn around result, keeping electric at 2.96 and raising gasoline to 3.61 cents per mile environmental cost - in other words, electric is actually 18% better.

Interesting point, but I would go further. I don't think they have fully allowed for the fact that the emissions from vehicles is so far past the point in which local ecosystems have the ability to handle, the factor should be raised exponentially.

How long do you think that battery would last for me? I'm guessing a battery for me wouldn't last 8 years.

Battery lifetime depends on charge cycles, not distance driven. You should know this.

Your usage would result in some deeper cycles, but on modern li-ions the difference would likely be negligible.

Of course the same is not true of traditional ICE, where your miles driven really will have a somewhat linear effect on lifetime, so I suspect the warrantee is more useless in the ICE case than the EV.

Is this a joke? The article doesn't contain a single number about the relative weight of the materials, or at all. The only numbers are dollar figures.

I reiterate my original question:

Perhaps you can name even one major mass market car that is mostly aluminum and/or plastic by weight?

Provide numbers, with useful references.

If you can find out how much the frame of an F150 weighs (the only large metal component that is still steel in that truck), you'll have your answer. Sadly, no one seems to break out their steel to aluminum weight ratios.

Which in turn makes me think that you made up your initial 75% ratio from thin air. So, quite frankly, at this point, I'd like you to support your number before I delve anymore deeply into the topic.

So, quite frankly, at this point, I'd like you to support your number before I delve anymore deeply into the topic.

= I cannot provide numbers with useful references so I will try a little misdirection...

Isn't that the 3rd dog in the 4 dog defense?

I was polite and did his research for him when I tried to find some data to either prove or disprove his initial numbers. The data I found was inconclusive as to hard numbers, but at least showed that his blanket statement of "all mass market vehicles are 75% steel or more" is dubious, at least.

So far, I've shown actually more supporting data than he did. Which makes your statement rather ironic.

Musk had stated before that while the battery does incur more emissions during manufacturing compared to an equivalent ICE vehicle, one breaks even around 5,000 miles. The Gigafactory is likely to change those figures again as the component materials will be sourced from North America and there will be less shipping distance to the factory.

The Gigafactory already rides on 1.25$ billion subsidies. How are we going to factor that in? Subsidies, tax cuts, tax credits.. Makes one wonder if the price actually went down or just the cost got crowdsourced...

So, quite frankly, at this point, I'd like you to support your number before I delve anymore deeply into the topic.

= I cannot provide numbers with useful references so I will try a little misdirection...

Isn't that the 3rd dog in the 4 dog defense?

I was polite and did his research for him when I tried to find some data to either prove or disprove his initial numbers. The data I found was inconclusive as to hard numbers, but at least showed that his blanket statement of "all mass market vehicles are 75% steel or more" is dubious, at least.

So far, I've shown actually more supporting data than he did. Which makes your statement rather ironic.